Some CD-R/RW recording apparatus emerged in recent years use zone CLV technology, which divides a recording area of a constant-linear-density-formatted disk recording medium into a plurality of sub-recording-areas (hereinafter referred to as zones) and records data in different zones at different constant recording speeds (recording rotation speeds) (see Japanese Patent Laid-Open No. 2001-176193, for example).
One conventional method for zoning and determine a recording speed for each zone is to divide the recording area into zones and determine a recording speed for each zone such that recording in the last zone is performed at the maximum recording speed specified for an apparatus or a disk recording medium in the last zone.
When a boundary between zones (speed change position) is detected to change the recording speed during recording, the recording is suspended, information about the recording speed for the next zone is used to change parameter settings, then a seek is done to a position before the speed change position, data is reproduced at a new recording rotation speed in the section from the seek position to the speed change position and servo controls are performed.
However, if zoning is done so that recording in the last zone is performed at the maximum recording speed specified for an apparatus or disk recording medium, the disk recording medium rotates more faster for recording in zones near the outer edge than for recording in zones near the center. Accordingly, when data is recorded on a poor-condition disk recording medium with a high axial run-out or eccentricity, the servo error may increase in zones nearer the outer edge of the disk recording medium and a servo failure may occur when servo control is performed. If such a servo failure occurs in a conventional recording apparatus, the apparatus makes a predetermined number of retries, then determines that the disk is non-recordable and ends the recording.
When a conventional disk recording apparatus detects an eccentricity during activation of a disk and determines based on the detection that data cannot be recorded on the disk at the maximum recording speed, it divides the recording area into zones and determines the recording speed for each zone in such a manner that the recording speed does not reaches the maximum recording speed in the last zone. However, this method has the problem that recording takes more time because recording in the last zone is performed at a lower speed than the maximum recording speed.
In the case of packet recording, if the packet recording ends at a position immediately following a recording speed change position, changing the recording speed can add to the recording time, depending on the amount of packet data.
In the case of track-at-once recording, after content data is recorded, a read-in area and then a read-out area are recorded as session closing process. A conventional disk recording apparatus changes the recording speed even if a speed change position is within the read-in or read-out area. In such a case, too much time is wasted in the session closing operations.
Furthermore, if buffer-under-run, which can occur when a host computer cannot steadily supply data during recording, occurs and recording is halted, the recording will be resumed at the position where the recording was halted at the same recording speed as before the halt. Depending on the condition of the disk recording medium, however, recording cannot be performed at the same speed as before halt. That is, if a buffer-under-run occurs, the recording apparatus must make a seek to a position before the position at which recording has been halted to resume the recording as same speed as before halt and reproduce data in the section from the seek position to the position at which the halt has occurred at the same rotation speed as before the halt in order to perform servo control. However, depending on the condition of the disk recording medium, such servo control cannot properly be performed and consequently a servo failure may occur. In such a case, a conventional disk recording apparatus makes a predetermined number of retries, then assumes the disk to be non-recordable, and ends recording.